Climate, Drift, and Image Data from Antarctic Icebergs A22A and UK211 , 2006-2007

Summary

This data set includes a variety of station data from two Antarctic icebergs. In 2006, researchers installed specialized weather stations called Automated Meteorological Ice Geophysical Observing Stations (AMIGOS) on two icebergs, A22A and UK211 (nicknamed Amigosberg), near Marambio Station in Antarctica.The AMIGOS stations were outfitted with Global Positioning System (GPS) sensors, cameras, and an electronic thermometer. They collected data from their installation in March 2006 until the icebergs crumbled into the ocean, in 2006 (Amigosberg) and 2007 (A22A). Available data include GPS, temperature and ablation measurements, and photographs of the station base and of flag lines extending out to the edges of the icebergs. Snow pit data from iceberg A22A is also included.

This data set was collected as part of a National Science Foundation Office of Polar Programs Special Grant for Exploratory Research, to explore the possibility of using drfting icebergs to investigate ice shelf evolution caused by climate change. The expedition, nicknamed IceTrek, was conducted jointly with Argentine scientists. The data are available via FTP in ASCII text (.txt) and Joint Photographic Experts Group (.jpg) formats.

Citing These Data

We kindly request that you cite the use of this data set in a publication using the following citation. For more information, see our Use and Copyright Web page.

The following example shows how to cite the use of this data set in a publication. List the principal investigators, year of data set release, publisher: NSIDC, and digital media.

Scambos, T., R. Bauer, R. Ross, J. Bohlander, J. Thom, Y. Yermolin. 2010. Climate, Drift, and Image Data from Antarctic Icebergs A22A and Amigosberg, 2006-2007. Boulder, Colorado, USA: National Snow and Ice Data Center. http://dx.doi.org/10.7265/N5N014GW.

Overview Table

Category Description
Data format Data are in ASCII text (.txt) and .jpg formats.
Spatial coverage and resolution Southernmost Latitude: 80° S
Northernmost Latitude: 47° S
Westernmost Longitude: 60° W
Easternmost Longitude: 15° W
Temporal coverage and resolution March 2006 to January 2007
File naming convention Amigos_gps.txt
20060218_02.jpg
File size Files range in size 4 KB from to 442 KB.
Parameter(s) GPS
Temperature
Degree Hours
Snow Ablation/Accumulation
Photographs
Procedures for obtaining data Data are available via FTP.

Table of Contents

  1. Contacts and Acknowledgments
  2. Detailed Data Description
  3. Data Access and Tools
  4. Data Acquisition and Processing
  5. References and Related Publications
  6. Document Information

1. Contacts and Acknowledgments

Investigators

Dr. Ted Scambos
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
Boulder, Colorado 80309
USA

Jennifer Bohlander
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
Boulder, Colorado 80309
USA

Rob Bauer
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
Boulder, Colorado 80309
USA

Ronald Ross
Polar66 8/788
New South Head Road
Rose Bay, NSW 2029
Australia

Dr. Jonathan Thom
947 Atmospheric, Oceanic, and Space Sciences Building
1225 West Dayton Street
Madison, Wisconsin 53706
USA

Dr. Yevgeniy Yermolin
Instituto Antartico Argentino
Cerrito 1248,
Buenos Aires 1010
Argentina

Technical Contact

NSIDC User Services
National Snow and Ice Data Center
CIRES, 449 UCB
University of Colorado
Boulder, CO 80309-0449  USA
phone: +1 303.492.6199
fax: +1 303.492.2468
form: Contact NSIDC User Services
e-mail: nsidc@nsidc.org

Acknowledgements

This research was supported by NSF OPP grant number 0540915 and NASA grant NNG06GA69G.

2. Detailed Data Description

Format

Data are in ASCII text format (.txt). Figures are available in Joint Photographic Experts Group (.jpg) format.

File and Directory Structure

Data are available on the FTP site in the ftp://sidads.colorado.edu/pub/DATASETS/AGDC/scambos_nsidc_0466/ directory. The folder contains ASCII text files, as well as image files within subfolders.

File Naming Convention

Text Files

ASCII text files are named according to the following convention and as described in Table 1:

iceberg_datatype_Y1_Y2.txt

Where:

Table 1. File Naming Convention for Text Files
Variable Description
iceberg Iceberg name: A22A or Amigosberg
datatype Type of data in file: GPS, depth, degree hours (deghrs), icepit data, or temperature
Y1 Year in which measurements began
Y2 Year in which measurements ended

Example: The file a22a_depth_06_07.txt contains depth measurements for the iceberg A22A, during the time period 2006 to 2007.

Image Folders

Image folders are labeled by iceberg and image type, according to the following convention and as described in Table 2:

iceberg_imagetype_imgs

Where:

Table 2. File Naming Convention for Image Folders
Variable Description
iceberg Iceberg name: A22A or Amigosberg
imagetype Direction of photograph:
Base: Photo looking down at the AMIGOS station base
Flag: Photo looking out over the flag line that extends towards the iceberg edge
imgs Folder contains image files

Example: The folder amigos_flags_imgs contains photos from the AMIGOS station on Amigosberg, looking out over the flag line that extends towards the iceberg edge.

Image Files

Each image file within its folder is named based on its date, according to the following convention and as described in Table 3:

YYYYMMDD_NN.jpg

Where:

Table 3. File Naming Convention for Image Files
Variable Description
YYYY Four-digit year
MM Two-digit month
DD Two-digit day
NN Photo number: 02 refers to flag images and 06 refers to base images

Example: The file 20060218_02.jpg is a photograph taken on 18 February 2006, looking out over the flag line that extends towards the iceberg edge.

File Size

Files range in size from 4 KB to 353 KB.

Spatial Coverage


Southernmost Latitude: 80° S
Northernmost Latitude: 47° S
Westernmost Longitude: 60° W
Easternmost Longitude: 15° W

Spatial Coverage Map

map of iceberg tracks

Figure 1.
This map shows the iceberg tracks in the Southern Ocean.
A22A is shown in green, and UK211 (Amigosberg) is shown in pink.
Tracking data courtesy D. Long.

Parameter or Variable

This data set contains GPS location data, temperature measurements, depth, and accumulation/ablation measurements, and snow pit data provided by Yevgeniy Yermolin. The data set also includes image taken by cameras on the AMIGOS station at pre-set times each day. Table 4 lists the parameters in each type of data file.

Parameter Description

Table 4. Parameter Description
Parameter Description
GPS
Time Time (UTM) in HHMMSS
Latitude Latitude, in degrees and minutes (DDDD.MMMM)
Longitude Longitude, in degrees and minutes (DDDDD.MMMM)
Speed Speed in kilometers per hour
Bearing Bearing, in degrees. Does not report when speed is 0.00 km/hr
Date Date (DDMMYY)
Temperature
ddoy Decimal day of year (Multiple measurements were taken each day)
temp Air temperature measurement in degreed Celsius
Depth
doy Numerical day of year (One measurement was taken per day)
depth Height of pole above snow surface in centimeters, with an initial setting of 75 cm above snow level
Degree Hours
ddoy Decimal day of year (Multiple measurements were taken each day)
deghrs Sum of hours per day during which the air temperature was above freezing.
Snow Pit
Firn Core Depth Firn core depth in meters
Firn Temperature Firn temperature in degrees Celsius
Snow Pit Depth Snow pit depth in meters
Firn Density Firn density in grams per cubic centimeter

Sample Data Record


Sample GPS data record from A22a_allgps.txt. This sample shows only the first four records in the file.

Time Latitude Longitude Speed Bearing Date
134816 6314.4952 S 05146.3772 W 000.4 334.5 190306
142818 6314.2754 S 05146.6103 W 000.4 332.4 190306
152821 6313.9972 S 05146.9818 W 000.3 322.9 190306
162825 6313.7942 S 05147.3498 W 000.0 313.3 190306

Sample Images

Base image of A
Figure 2. Photograph of A22A AMIGOS Station Base, taken on 1 December 2006.

flag line photo from A22a
Figure 3. Photograph of flag line on A22A, taken on 14 November 2006.

3. Data Access and Tools

Data Access

Data are available via FTP.

Volume

The total volume of this data set is 8.3 MB.

Software and Tools

Data are accessible using spreadsheet software. Image files may require image viewing software.

Related Data Collections

4. Data Acquisition and Processing

Theory of Measurements

Measurements were made using an automated system of weather sensors, GPS, and cameras mounted on towers on two icebergs in the Southern Ocean. More details on the methods are available in Scambos, et. al., 2008.

5. References and Related Publications

Scambos, T., R. Ross, R. Bauer, Y. Yermolin, P. Skvarca, D. Long, J. Bohlander, T. Haran. 2008. Calving and Ice Shelf Break-Up Processes Investigated by Proxy: Antarctic Tabular Iceberg Evolution during Northward Drift. Journal of Glaciology, 54 (187) 579-591.

The following related documents are available on the NSIDC Web site:

Table 4. Related Documents
Document Description URL
Antarctic Glaciological Data Center (AGDC) Data Center Web site http://nsidc.org/agdc/
IceTrek IceTrek Expedition Informational Web site http://nsidc.org/icetrek/

6. Document Information

Acronyms

The following acronyms are used in this document.

Table 5. Acronyms and Abbreviations
Acronym Description
AGDC Antarctic Glaciological Data Center
AMIGOS Automated Meteorological Ice Geophysical Observing Station
FTP File Transfer Protocol
NSIDC National Snow and Ice Data Center
URL Uniform Resource Locator

Document Creation Date

January 2011

Document URL

http://nsidc.org/data/docs/agdc/nsidc0466_scambos/index.html